Corrugated cardboard boxes are well known and are commonly used to store and ship various goods such as produce. Such boxes are typically made from a single sheet of corrugated cardboard, referred to as a blank, that is cut, scored, and then folded along the score lines into a certain shape where it is then glued or otherwise held together. One problem associated with such boxes is their lack of vertical strength, which precludes stacking of full boxes beyond a certain height, necessitating additional supports or shipping pallets to prevent damage to the contents of the boxes.
One box design that attempts to solve the aforementioned problem is the produce container disclosed in U.S. Pat. No. 5,002,224 to Muise. Muise discloses a cardboard container that provides improved vertical support by including an additional vertical support section hingedly attached to the end panels of the container. Each vertical support section of Muise consists of two narrow vertical panels set at a 90 degree angle to the end panel with one of the narrow vertical panels having a tab member hingedly attached to the top of the narrow vertical panel. Each tab member forms a horizontal corner platform that transfers vertical loads to the narrow vertical panels. Each tab member also includes an extension that overlies a portion of the top edge of the adjacent end panel to transfer vertical loads to the end panel as well.
While Muise provides more vertical stacking support than a typical non-reinforced cardboard box, the Muise design leaves room for improvement. Because the vertical support panels of Muise only extend in one direction relative to the end panel, there is little provision for lateral stress on the container. Lateral stress may distort or bend the hinged vertical supports, which may result in collapse of the container and damage to the contents. Additionally, the tab member of Muise does not carry any vertical loads by itself but only transfers loads to adjacent panels through its connection to the vertical support and its extension resting atop the end panel. Therefore, the tab member and its extension are for the most part unnecessary, merely acting as an additional layer of box top. Thus, there is a need for an improved vertical corner support in a box formed from a single sheet of corrugated cardboard.